Thomson



UNITED STATES PATENT JOHN THOMSON AND CHESTER H. EVANS, OF SAN FRANCISCO, CAL.

STEAM PUMPlNG-ENGINE.

SPECIFICATION forming part of Letters Patent N0.1243,814, dated July 5, 1881.

Application filed November '7, 1879.

To all whom it may concern Be it known that we, JOHN THOMSON and CHESTER H. EvANs, both of the city of San Francisco, State of California, have invented a new and useful Improvement in Steam Pumping-Engines, of which the following is a specication.

The invention relates to that class of pumps used in deep wells or for submerged pumps located in the water and used to force water up.

The invention will be understood as set forth in the following specification and claims.

ln the accompanying drawings, Figure l is an elevation of the engine and pump together. Fig. 2 is a detail ot' the engine.

P represents the pump-barrel, r the pistonrod, L the discharge-pipe. t fi are suspendingrods supporting the plate d, on which rests the spring I), and bears against the head Z on the rod r above. The rods t' t' may be adjusted by means of bolts on their lower ends to any length.

Fig. l shows a pump and engine combined, the object of the engine being to impart a reciprocating motion to the pumprod r, the engine E having a cross-head, H, which gives a rotary motion to the shaft F', and so that a continuous rod, r, can be used for the pump P and the piston of the engine E; also, in the manner of connecting the crank that rotates the shaft F and ily-wheel F to the cross-head.

In Fig. 1, Fis the ily-wheel, hung on a shaft, on the opposite end of which shaft is fixed the crank K. The said crank is provided with a wristpin which works into half-boxes b, that are made to slide in the cross-head H. In between one of the boxes and the cross-head H is inserted a wedge, w, which is provided with a gib-head, and through said head is passed a stud which is rigidly screwed into one of the boxes b' that is on the side next to w. The stud o is provided with a nut, which, being screwed down, presses the wedge between the box b and cross-head H, thus tightening the box b' on the crank-pin, andalso tightening the box in the slide of the cross-head H. In order to keep the wedge firm in its place we insert a string of thin washers around the bolt o and between the head of 'w and the box b',

o so that as the nut is screwed down tightly it closes the head of w firmly on the washers between the head, and box b', thus making it t closely in the cross-head H, and causing the box b and wedge to be rigidly connected together. move one or more of the washers and screw the wedge down on the remainder. In this case we use a common slide-valve (not shown) which is worked by an eccentric pla-ced on the shaft of the fly-wheel.

The weight of the piston and long rod superadded to the force of the engine make the downward stroke of the piston much more forcible than the upward, and to counterbalance this we have provided a counterbalancing spring, D. This spring is a coil wound about the rod r, and resting upon a strap or plate, a, which is swung from the frame of the pump by the rods t' t'. At its upper end the springs bear against a collar, l, rigidly xed to the rod r. This prevents a sudden descent, and,v recoiling, aids in lifting the piston on the upward stroke.

Fig. 2 shows the cross-head and the manner of connecting the same to a continuous rod, r, also the bearings B B, eccentric f, and crank k, around the ily-wheel shaft, also the arm p, which slides in the frame m, and keeps the cross-head H from turning.

We purpose to make the pump the subg'ec of a separate application.

What we claim as our invention is- 1. The cylindrical pump and engine E, having a continuous piston-rod, r, in combination with the head H and boxes b, wedge w, stud o, and washer t, operating the crank 7c, thereby rotating the shaft F', ily-wheel F, and valveeccentric f, substantially as shown and described.

2. The counterbalance-sprin g D coiled round the rod r, and sustained by the adjusting-rods t' and by the plate d, said spring pressing gailnst the collar Z, secured to rod r, as set ort JOHN THOMSON. `CHESTER HEPBURN EVANS.

Witnesses P. MEAGHEE, J. ROBERT READ.

In case slackness should occur, we re-` 

